1. Field of the Invention
Apparatuses and methods consistent with the present general inventive concept relate to an image forming apparatus and an image forming method thereof, and more particularly, to an image forming apparatus to identify an unwarranted toner, and an image forming method thereof.
2. Description of the Related Art
An image forming apparatus forms an image based on printing data. An image forming unit of the image forming apparatus forms an image. The image forming unit includes a photosensitive body which forms an electrostatic latent image thereon, a light scanner which scans light to form the electrostatic latent image on the photosensitive body, a developing part which applies a developer to the electrostatic latent image formed on the photosensitive body, and a cartridge which stores toner therein.
A user may purchase a cheap unwarranted toner for the image forming apparatus. However, the unwarranted toner has characteristics different from a warranted toner. Since the durability of the photosensitive body and the developing part of the image forming unit is designed corresponding to an amount of the warranted toner which is provided initially, the frequent use of the unwarranted toner may cause unnecessary wear of the photosensitive body and the developing part. Also, the cleaning and charging operations of the photosensitive body is not performed properly, thereby deteriorating quality of an image formed by the image forming unit.
If the image is deteriorated as described above, a user may not perceive that the unwarranted toner is the cause. Instead, a user may ascribe the problem to the image forming apparatus itself. Also, an improper development to the photosensitive body due to the unwarranted toner may contaminate the image forming apparatus by scattering of the toner and carrier carrying the toner.
Thus, a conventional image forming apparatus adopts a method of not outputting an image when reaching a critical value in durability of the photosensitive body and to prevent the developing part from using the unwarranted toner. However, this method is against a law in some countries including Europe. Therefore, it is necessary to maintain a quality of an image at a certain level even if the unwarranted toner is used.